Protein Chip

In contrast to the MALDl technique, where the surface of the probe does not have an active role in the analytical process beyond holding the sample, in SELDI the probe surface plays an active role in a number of aspects of the processing of the analytes, e.g., extraction, structural modification, and amplification [14]. In the 

ProteinChip technology [15] special array surfaces are used to selectively retain entire subsets of proteins directly, and in a single step from biological samples. Thus, in contrast to HPLC-MS, which combines elution chromatography with MS, SELDI-MS combines retention chromatography with MS. 

Whatever analytical approach is used for the characterization of proteins, the common last step is to use a computer algorithm for the evaluation of the data obtained [24]. The general role of bioinformatics in protein analysis, including database searches, sequence comparisons, and structural predictions, has been reviewed [25,26]. A concise review of the available software tools for database searching to interpret mass spectrometric data lists relevant original references [25]. 

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The development of protein chip assays to determine protein function using purified components is a rapidly advancing area. Automated systems for the assay of protein function on chips in parallel for thousands of proteins simultaneously will likely be available in the next few years. These miniaturized arrays will be useful for basic research as well as for diagnostics and drug development. For instance, the combination of protein chips with combinatorial chemistry will allow the simultaneous screening of vast collections of small molecules against vast collections of potential target proteins. 

Zhu H et al. Analysis of yeast protein kinases using protein chips. Nature Genet 2000 26 283-289. 

Zhu, H., and Snyder, M. (2003). Protein chip technology. Curr. Opin. Chem. Biol. 7, 55-63. 

Biochips can be used for either measuring differential expression between two populations or for testing for the presence of a DNA sequence (resequencing). Protein chips have been applied in expression profiling and antibody detection, binding specificities of a protein expression library and protein-protein interactions. 

Monoclonal and polyclonal antibodies serve as specific affinity ligands in protein chips. Though monoclonal/polyclonal pairs are more readily available than monoclonal/monoclonal pairs, polyclonal antibodies often cause higher background and lower sensitivity and specificity. 

Duan, L., Wang, Y., Li, S.S-C., Wan, Z., and Zhai, J. (2005) Rapid and simultaneous detection of human hepatitis B virus and hepatitis C virus antibodies based on a protein chip assay using nano-gold immunological amplification and silver staining method. BMC Infect. Dis. 5, 53. http //www.biomedcentral. com/1471-2334/5/53. 

Srikant, P., Singh, A.K., McElhanon, J.R., and Dentinger, P.M. (2004) Dendrimer-activated surfaces for high density and high activity protein chip applications. Langmuir 20(15), 6075-6079. 

K.Y. Park, M.S. Kim, and S.Y. Choi, Fabrication and characteristics of MOSFET protein chip for detection of ribosomal protein. Biosens. Bioelectron. 20, 2111-2115 (2005). 

Capture array Non-protein molecules that interact with proteins are immobilized on the surface. These may be broad capture agents based on surface chemistries such as the Ciphergen Protein Chip, or may be highly specific such as molecular imprinted polymers or oligonucleotide aptamers... 

The use of biochips in basic biological research has provided information that was heretofore inaccessible. Protein chips, especially functional microarrays, are used to... 

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